(1) Field of the Invention
The invention relates to mobile home ceiling construction providing a concealed, back fastened, ready-to-install ceiling unit and method for manufacturing said ceiling unit.
(2) Description of the Prior Art
The increased desirability for mobile home living in recent years has been in part created by the ability of mobile home manufacturers to provide interior accommodations comparable to conventional building construction. One particular aspect of mobile home construction which has provided problems involves the ceiling system. With the increased lengths and widths of room sizes it has become an industry wide concern to provide a ceiling which is aesthetically pleasing as well as structurally sound.
Concealment of the required attachment elements for supporting ceiling panels has been a continuing concern and has been somewhat attained through numerous prior attempts. However, the solutions involved disguising nails, staples, screws, wires and the like, by covering them with splines, battens, rosettes, and other similar exposed cosmetic devices.
Additionally, when the industry has attempted to entirely eliminate any exposed artifices it has provided back face fastening means which unfortunately created additional problems. The most common problem with the back fastening techniques disclosed in the prior art involves the necessity of providing non-conventional specialized ceiling panels. Conventional panels are usually comprised of gypsum, wood fiber, mineral fiber, pressed paper, and other widely known construction materials. These are typically manufactured in predetermined lengths and widths employing simple rectangular shapes. It has become problematic to adapt concealed back fastening techniques to conventional panels. It would be highly desirable to avoid costly additional manufacturing steps required to prepare special panels to receive particular concealed fastening devices.
Less complex back fastening systems have been provided and utilize adhesive materials connecting the back faces of the panels to roof frame truss members. Problems with these adhesives involve the delay of drying or set-up time and thus slowing down the manufacture. Additionally, when subjected to extreme heat, such as experienced in a fire, the bonding between the back faces of the panels and truss members is lost and the ceiling system quickly fails.
One prior art solution to back fastening is disclosed in U.S. Pat. No. 4,033,083, wherein conventional four foot wide sheets of ceiling board are back fastened. The practice of this invention however requires that the ceiling boards have cuts in the back faces to receive particularly shaped angled flanges of fastening devices. The conventional ceiling board must be subjected to additional manufacturing steps for use therein. Another attempt at eliminating face exposed fasteners is disclosed in U.S. Pat. No. 3,826,055. This patent requires a flexible sheet to be adhered to the back face of panels and crimped at truss locations to provide flaps whereby fasteners penetrate the flaps for engagement to truss members. The sheet material must necessarily be flexible in order to be folded to provide the flaps at truss spacing intervals. The teaching of this prior art system eliminates exposed fasteners and can provide a vapor barrier. However, the fastening of the panels is dependent upon the strength and heat resistance of the flexible material since it is the connective means between the panel and truss. Failure therein would necessarily cause the system to fail by the panels disengagement from the framing.
Other older prior art systems having mechanical fastenings concealed from view utilize metal pronged devices. One such system is disclosed in U.S. Pat. No. 1,297,523. This patent discloses a plate having upper and lower prongs. The upper prongs are inserted initially into truss members and then ceiling panels are forced upwardly against the lower prongs and hammered into place. This system provides concealed fastening but prevents placement of a vapor barrier material above and additionally precludes fabricating a unitized ceiling structure.
Another older system effecting concealed fastening is disclosed in U.S. Pat. No. 1,790,348. In this disclosure a similar technique is utilized wherein a slotted staple is first affixed to truss members and depending prongs are then forced into engagement with upper ceiling panel surfaces. In this disclosure, as well as in the aforementioned U.S. Pat. No. 1,297,523, deformation of the front face of the panels can occur during the driving of the panels upwardly into engagement with the prongs. Additionally, flush joints between panels may become difficult to obtain and the rudimentary construction techniques prohibit attaining close tolerances.
It is thus evident from the prior art attempts to solve all the needs of the mobile home construction industry that a unitized ceiling structure having concealed back fastening with vapor barrier adaptability is not found. Prior art attempts at providing concealed back fastening introduce additional manufacturing problems regarding the alteration of conventional ceiling panels. It would be desirable to utilize conventional panels in a unitized ceiling structure having flush joints and concealed back fastenings capable of providing a vapor barrier and capable of prefabricated modular use involving no additional drying or set time for adhesives.